Process of manufacturing car-wheel blanks.



H. R. KEITHLEY.

Patented Nov. 8, 1910.

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HERBERT R..- KEITHLEY, F KANSAS Y, MISSOURI;

PROCESS 0F MANUFACTURING CARWHEEL BLANKS.

To all ivhom 'it may concern:

Be itknown that I, HERBERT R. KEITH- Lex', a citizen of the UnitedStates, residing at Kansas City. in the county of Jackson and State ofMissouri, have invented certain new and useful Improvements in Processesf Manufacturing Car-Viheel Blanks, of which thefolloiving` is a full,clear, and exact description.

In the present state of the art, it is impracticabie-to produceeconomically, sound and efficient car-wheels from steel castings or castblanks, on account of the great difficulty of securing a homogeneous andsolid structure 'in the cast blank. As a consequence the blank fromwhich the car-Wheel i-s made must: be subjected to a previous rolling orforging operation before being subjected to the pressure of the diesWhich give vthe blank the rudimentary form of a carivheel, and thereforethe initial heat of the blank, due to casting, cannot be' retained untilthe initial die forging 'operation is erformed and the blank is requiredto be reiieated. This necessity of re-heating the blank vafter it haslost its initial heat due' to casting, limits the carbon content andcon,- seqnently th 1 hardness of the steel-Which can be used in presentmethods ofproducing carwheels, to such an extent that comparativelylsoft steel is used. This isprincipally due to the fact that the hardersteel must not, on account of its higher carbon content, be heated ashighly and must therefore be forged at la lower temperature. At suchlower temperature the resistance lof the harder steel to4 forgingpressures increases more rapidly `with declining temperatures than itdoes with` mild steel.- its a consequence if harder steel were usedin'Iorder tol give it the degree ezt-plasticity required for the heavyforging pressures ofthe initial die'forging operation, itvvouldhave tobe heated to a high 'temperature y at-Which there would be danger ofover-heating or-lournin the steel. in my improved process thisdifficulty is'obviated by my method of producing a sound homogeneoussteel cast blank which may be removed from the moldA to the diesandeuhjected to the initial die forging operation while it retains itsinitial heat dueto 'casting'9 and While` it retains a high degree ofplasticity Which'coiild not be attained by rfa-heatingl the 'blankwithout Specification of Letters Patent. Y

ldanger of overheating and burning hard steels having high carboncontent or hard steel alloys. The 'more especial object of my invention1s to provide new and improved processes of manufacture Which will makehard steel :vnd its alloys, and preferably manganese steel, availableand their use practicable and economical for producing car-wheels forrailroad cais.

Manganese steel containing from G to 12 per leent. or more, of manganesepossesses properties-of intense hardness and great resistance toabrasion and Wear. These qualities are essential in the Wearing bodyportion of the rim and flange of a car-Wheel for railroad cars. i

Heretofore manganese steel has had only a limited use for car-Wheels formine cars, and could only be'adapted for this use by casting themanganese steel Wheel With a soft steel hub portion in Which the axlehole could be cored and finished by machining or could be bored out. Forthe' manganese steel, owing to its intense hardness, is 'practicallyuninachineable and cutting or boring tools have no effect upon it. As aconse-v quence of the difficulty of finishing this steel which can bedone only by a grinding operation, it is iinpracticable to produce, witheconomy, carwheels from manganese steel by present processes ofmanufacture,

yIn carrying out my invention l produce, -bycasting, a blank ofpreferably circular form and substantially uniform thickness and of lessdiameterthan the finished Wheel v it is to form, and free from pipings,blow holes and other imperfections, and while hot the blank may .then`be removed from' the jmold and subjected to the heavy forging pressureof the initial die forging operation which produces the 'rudimentaryhub, web `and rim of a car-Wheel in the blank, While it retains theinitial heat due to casting. l In the accompanying drawings,illustrating my invention, in the several lires of vwhich like partsare'similarly designated, Figure l is a vertical sectional view showinga mold of special construction for producing steel cast blanks,according to m invention, which will be freefrom ipes, lowholes,shrinkage cavities, and ot ver defects., and from which car- Wheels maybe produced according to my invention. Figt 2' is a lverllatented Nov'.8, 19MB..

Application filed August 19, 1909. Serial No. 513,701.

cast blank partly forged by said dies, so as to form the rudimentaryhub, web and rim portions of a car-wheel according to` my iuvention.Fig. 4 shows the partly forged steel castblank in vertical section, whenremoved from the dies, Fig. 3.

Referring to the accompanying drawings in detail, the steel cast blankC1 Fig. 2, is formed with a horizontal circularbody pory-tion and avertical column portion having greater 'thickness and is.preferably'cast in a specially yconstructed mold, Fig.- 1, in

.which the cope A and drag' B'. are made of castironand-the riser Al-ispreferably made "of sand or Ifire clay or similar refractory orheatzfretaining material'. Thismold forms a circular chamber C with 'awide opening,

formed by the riser A1.' When the molten ysteel is poured intothezchamber C themetal in'contact with the cast iron chills A and B'-fsolidiies`-much more rapidly than in the central portions c1 c1 andthe thicker column portion al in the riser A1, the layers of solidifiedmetal formed each minute after 'the metal is' poured are indicated bythe dotted lines .1. 2. 3., Fi 1. TheV outer portions of the steel castb ank are rapidly contracted by contact 'with the chills A and B andexert such great'pressure inwardly upon the still Huid metall of theinterior lower portions o1 a? of the casting that no pipes o1 lshrinkage cavities will vform in the lower interior portions of thelcasting. The hydrostatic pressure of the Huid metalin the riser A1 willfeed the fluid metal into the-interior fluid portions 01 cl'untilthe-entire lower part of the casting is solidied 'and all pipes,shrinkage cavities and other'defects will be .forced into the riser A1and the=column of metal containing these defects can be discarded bycropping off when the casting is removed'from the vmold, leaving thewhole lower portion of the casting in the form of a circular blank,sound and free from all defects and' ready for forging into a4 carwheel.The cope A ispreferably supported upon 55 two cams b1 b'carried bythe'shaft b2; to

Which the lever b3 is-attached. vWhen the molten steel is `pourcd'intovthe chamber C the portion in contact with the" cast iron cope A will`tend to shrinkdown' from the casting, and in order to prevent theforming of a space 'between the cast-in fand the co e A in which" gas.bubbles mig leverb3 is operated to turnthe cams b1 b1 on the shaft b2so the weight of the cope A will continue to .rest directly upon the 5metal as it solidiies anditends to' shrink t collect, t e5 away from thecast iron cope A. By thismeans the blank will be uniformly chilled bothfrom the -top and the bottom and the casting will be' given a uniformstructure.

Although the cope and drag of the mold are described above as preferablyconstructed of cast iron, sand, fire clay or other refractorymaterialmay be used if desired. The steel cast blank when produced frommanganese steel or similar hard steel alloy is preferably removed fromthe mold and the discard cropped off and then forged in the firstoperation forging'dies, Fig. 2, while still retaining its initlal heatfrom casting. By thi'smethod the hard steel can be subjected to theheavy pressure of the initial die vforging operation at muchfhigher'temperatures and consequently when in a softer andmore' plastic statethan would be practicable if it were :necessary to re-heat the blank. 1

The cast blank C1 is forged 'in the dies D. E., Fig. 2,- Which areoperated by hy- Adraulic pressure, thus formino' the rudimentary hubportion c1 I l with the hub portion c1 on onevside 1 of the' webc2 c2and the annular concave cavity c4 producing the rim portion c3 c3 andthe web 7 portion c2 c2 of a car-wheel, Fig. 3, by pressure betweenthedie portions' e2 e? d2 (Z2.

lfVhen the partly forged blank, Fig. 4 is removed 'fromtherst forgingdies D. E., Fig. 3, it may be subjected to further forging or rollingoperations to complete tho wheel. y

It is obvious that car-wheels may be produced 'according to my inventionfrom other hard steel alloys 'than manganese steel, which areunmachineable', also from `soft steel. y

In all steel car-Wheels at'pre's'ent produced by forging the wheel intoshape in order to give the required ductilityto the steel the and web.02, Fig. 3,

' is formed in the hubv .portion cl'by means of i .the annular convex'projection d?.

from a'blan ,l'm'ade according to my invention the wearing 4body of thewheel rim can be made as lightlas the-ri'rnof a chilled cast ironcar-wheel with a corresponding economy in weight and cost of metal.-H

erases.

than it would be practicable to re-heat a cold lilank to, for forginghard steel alloys or steels pf higher carbonv content thannoiv used forproducing car-Wheels, and with this operationof'retaining the initialheat of the metal, from feasting, and raising it to a higher temperatureafter the removal of the i blank from the mold, which is involved in myprocess, all danger of overheating or' burning the steel Will bebviated.

In a ear-wheel produced from a blank made according to my invention themetal may be subject-ed to heat-treatment, if required, when the Wheelis forged into shape by heating it to a propertemperature and thensuddenly cooling the metal by quenchin e. However itis believed that thechillingv effect of the metal forging-dies will. be sufficient lto givethe toughness and tensile strength desired for manganese steel, withoutre-heating the forged wheel to temper it. over-heating and cracking themetal by relie-ating will be obviatcd.

I claim as my invention and desire to secure by\ Letters Patent- 1. Tliemethod of producing an individual car wheel blank `free from pipes andsegregations which consists .in casting a horizontal steel disk with `avertieahcolumn rising fromthe top thereof, the parts being soproportioned that; tylie-v` metal. in"` the column remains fluidkuntilthe disk has solidified and the solidification of the disk`progresses from the edge thereof towardlfthe column, and thendiscardingathe coluifn.

2. The method o f producingan individual lcar Wheel blank free frompipes and segregations which consists in cast-inigr a horizontal steeldisk-With al vertical column of considerable crdss-sectional area risingfrom the top thereofat the center, the column being so proportionedythat theanetal therein remains fluid until the disk has solidified andthe disk being so shaped that solidiication thereof progresses from theedge toward the center so as'to avoi'dthe formation of solidifiedportions in the disk between the `fluid column and unsolidified portionsof the disk, and then discarding` the column.

3. The method of prdiicing an individual c'ar Wheel blank free from]pipes and segregations"-'Wliich consists in c'astinga horizontal steeldisk whichrises gradually toward the center and there merges into avertical column extending directly upwardly there'- from, the partsbeing so proportioned that Ithe column remains fluid until the disk hassolidified, and solidification'of the disk pro- 4If this result isattained all danger of -gresses from the edget-hereof .toward thecenter, and then discarding the column.

4. The method of producing anindividual car Wheel'blank free from' pipesand segregations Which consists in casting a horizontal steel disk witha vertical column rising from the :top thereof, the parts being soproportioned that the metal in the columnci'emains fluid until thediskhas solidified and the solidification of'the disk progresses from theedge thereof toward the column, subjecting the disk to pressure while itis solidifying, and then discarding the column. 5. The method ofroducing an individual car Wheel blank which consists in casting ahorizontal shallow' steel disk which rises gradually from the edgetoward vthe center and there merges into a vertical column extendingupwardly therefrom, the parts being so proportioned that the columnremains iuidl until the disk has solidified and solidiication of thedisk progressing from the edge thereof toward the cen-ter, vand thendiscarding the column.

6. The method of manufacturing an individual car wheel blank whichconsists lin casting a blank iii such form as to cause l solidificationof the metal to take place lprogressively from the entire outersurfaceto- Ward a common point so as to subjectv the progressivelydecreasing mass of molten metal in the interior of the blank tocoinpression toward said point, providing a vertical column of metal atsaid point so as to produce al hydrostatic head of metal acting upon themolten interior of the blank. and maintaining a portion at least of thecolumn in a fluid condition until ythe blank has solidified.

7. The method of manufacturing an individual car Wheel blank whichconsists in casting a blank in such form as to cause solidification ofthe metal to take place p rogressively from the entire outer surfacetoward a common point so as to,.subject the progressively decreasing'mass of molten metal in the interior of the. blank to conipressiontoward said point., providing avertical columii of metal at said pointso asto produce a hydrostatic head of metal acting upon the molteninterior of the blank, and causing the column to solidify more slowlythan the blank.

S. The method of manufacturing an individual ear Wheel blank whichconsists in casting a blank in such form as to cause solidification ofthe metal to take place progressively from the entireouter surface to-Warda `common pointso as to subject the .progressively decreasing massof molten column being made suiiciently large in cross section to causethe central portion thereof to remain iuidV until the blank hassolidicd.

9. The method of producing an individual car wheel blank which consistsin making a casting of molten steel having a much I from the top andbot-tom toward the interior and subject the progressively decreasingmolten mass in the interior of the casting to compression stresseswhich, together with the hydrostatic head Of molten metal in the column,serve to compact the metal as it solidiies and at the ysame time permitthe pipings and segregations to escape into' the column. i l c l .10,The method` of producing an individual car wheel blank which consists incasting a blank of substantially uniform vertical thickness .and havinga much greater horizontal thickness than vertical thickness, providing avertical column which rises rom the top of the blank, and chilling theblank, from the top and bottom faces so as to cause the solidilicationof the molten metal to take place progressively from the. top and bottomfaces of the blan, and .causing the flJlullpn to solidify more slowly'-than the 11. The method of manufacturing an iiidividual car Wheelblankwhich consists in making a casting of molten metal, chilling the castingfrom the top and bottom faces and from the sides so as to cause thecasting to' solidify progressively from the entire Outer surface towardacommon point and thereby subject the progressively decreas-- ing mass ofmolten metal in the lnterior of the casting to compression toward saidpoint,

' more slowly than t-he casti 12. vThe method of pr ucing an indi'vidual car wheel blank which consists in making a casting in the form ofa horizontal diskvhaving a much greater diameter than during cooling.

causing the column to solidify vertical thickness, subjecting the topVand bottom faces and the periphery of the disk to a chilling action soas to cause the molten metal to solidify progressively from the Outersurfaces of the disk toward the center of the disk and thereby subjectthe progressively decreasing mass of molten metal in the interiorof thedisk to. compression tO- ward the center, providing a vertical column ofmetal rising from the top of the disk at t-he center thereof so 'as toproduce a hydrostatic head of metall acting upon the molten interior ofthe disk, and causing the metal ofthe column to solidify more slowlythan the metal in the disk.

13. .The methodof producing an individual car wheel blank which consistsin making a casting of molten metal, providinga vertical columnextending upwardly from the top of the casting, chilling the rimportions of the casting and also portions be-- -to compression stressescoperating with the hydrostatic head of the molten metal in the columnto compress the molten interior of the blank, and causing the column tosolidify more slowly than the casting.

14. The method of manufacturing an individual. carwheel blank whichconsists in vcastinga blank having a much greater horizontal thicknessthan vertical thickness, chilling the blank from the top and bottom andfrom the sides so as tO cause the metal to solidify progressively fromthe outer surfaces to a common point and thereby subject theprogressively-decreasing molten mass in the interior of the blank tocompression toward said point, maintaining a Vertical .column of moltenmetal rising directly from the top of the blank at said point so as tosubject the molten interior of the blank to a hydrostatic head Aofmolten metal, and subjecting the lblank to external pressure Intestimony whereof I hereunto set my hand this eighth day of May, A. D.1909.

HERBERT R. KEITHLEY.

Witnesses:

.JOHN S. COOPER,

S. A. BISHOP.

